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A071340 a(n) = least positive r <= n such that the origin-centered circle of radius sqrt(r) touches A071339(n) lattice points. 1
0, 1, 1, 5, 5, 25, 25, 25, 25, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..52.

Hugo Pfoertner, Illustration

EXAMPLE

a(4)=5 because the smallest circle to touch A071339(4)=8 points has radius sqrt(5).

PROG

(FORTRAN) See A071339.

CROSSREFS

Cf. A071339-A071347.

Sequence in context: A256135 A227076 A223186 * A056451 A074872 A162962

Adjacent sequences:  A071337 A071338 A071339 * A071341 A071342 A071343

KEYWORD

easy,nonn

AUTHOR

Hugo Pfoertner, May 22 2002

EXTENSIONS

Edited by Don Reble (djr(AT)nk.ca), Nov 06 2005

STATUS

approved

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Last modified December 7 14:52 EST 2016. Contains 278877 sequences.